Subclinical hyperthyroidism: current concepts and scintigraphic imaging.

Subclinical hyperthyroidism is defined as normal serum free thyroxine and a free triiodothyronine level, with a thyroid-stimulating hormone level suppressed below the normal range and is usually undetectable. Although patients with this diagnosis have no or few signs and symptoms of overt thyrotoxicosis, there is sufficient evidence that it is associated with a relatively higher risk of supraventricular arrhythmias as well as the acceleration or the development of osteoporosis. Consequently, the approach to the patient with subclinical hyperthyroidism is controversial, that is, therapeutic intervention versus watchful waiting. Regardless, it is imperative for the referring physician to identify the causative thyroid disorder. This is optimally accomplished by a functional study, namely scintigraphy. Recognition of the scan findings of the various causes of subclinical hyperthyroidism enables the imaging specialist to help in diagnosing the underlying condition causing thyroid-stimulating hormone suppression thereby facilitating the workup and management of this thyroid disorder.

Lymphoscintigraphy in cutaneous melanoma: an updated total body atlas of sentinel node mapping.

Lymphoscintigraphy has become part of the standard of care for patients with a new or recurrent diagnosis of melanoma, in helping determine the status of regional lymph nodes. Correct identification of sentinel lymph nodes enables the surgeon to further delineate the extent of malignancy by allowing sampling of the appropriate nodal group. Performing the lymphoscintigraphy prior to the planned operation allows limited surgery with less extensive postoperative morbidity. For this reason, a thorough knowledge of the lymph node drainage patterns from the different primary tumor locations, as well as of proper lymphoscintigraphic techniques and radiopharmaceuticals, constitutes an important armamentarium in the hands of surgeons, radiologists, and nuclear medicine physicians.

Current immunotherapeutic strategies for central nervous system tumors.

Immunotherapy has emerged as a promising tool in the management of malignant central nervous system tumors. Despite improvement in patient survival, traditional approaches, which consist mostly of surgery, radiotherapy, and chemotherapy, have been largely unsuccessful in permanently controlling these aggressive tumors. Immunotherapeutic strategies offer not only a novel approach but also an advantage in a way other modalities have been failing. Specifically, the capabilities of the immune system to recognize altered cells while leaving normal cells intact offer tremendous advantage over the conventional therapeutic approaches. This article summarizes our current understanding of immunotherapeutic treatment modalities used in clinical trials for management of malignant central nervous system tumors.

Placement of subdural electrode grids for seizure focus localization in patients with a large arachnoid cyst. Technical note.

Subdural electrode arrays are placed to localize seizure foci for possible resection. The procedure is usually straightforward when an electrode grid array is placed on the brain convexity but can become complicated if the surface on which the grids are applied is not convex. Arachnoid cysts can be associated with seizures, but their topography presents a challenge to standard techniques for the placement of subdural grids. The authors report on a technique for electrode grid placement that successfully localized seizure foci in the depths of arachnoid cysts in two patients. Subdural grids were placed to conform to the concave cyst cavity. They were held in place with rolled gelatin foam padding, which filled the arachnoid cyst. The padding was removed before removing the electrode grids and resecting the seizure focus. Although arachnoid cysts present a technical challenge when seizure foci are located within the cyst cavity, the technique of packing the cyst cavity with gelatin foam provides good electrode contact on the concave cyst wall, allowing adequate seizure focus localization.

Ewing's sarcoma of the cavernous sinus: case report.

OBJECTIVE AND IMPORTANCE: The Ewing's sarcoma (ES) family of tumors is a relatively rare entity, presenting most commonly in children. While the most common sites for this group of tumors are the trunk and the extremities, this case is unique in that we describe a long-term follow-up with an ES presenting in the cavernous sinus. CLINICAL PRESENTATION: We report the case of a 13-year-old girl presenting with the symptoms of classic orbital apex syndrome. Magnetic resonance imaging disclosed a cavernous sinus mass engulfing the optic nerve and extending into the superior orbital fissure. INTERVENTION: Evaluation of this patient included intracranial magnetic resonance imaging angiography and biopsy of the cavernous sinus mass lesion. Histopathological findings yielded a diagnosis of ES. Further work-up demonstrated that the patient's thyroid was also involved. The tumor was treated with radiation therapy to both sites and, subsequently, after confirmed metastases to other sites, 11 cycles of doxorubicin-based chemotherapy, as well as bone marrow transplantation. However, the patient succumbed to the illness 18 months after her initial diagnosis. CONCLUSION: The cavernous sinus is an unusual site for ES, but given the vascularity and the frequency of this tumor in childhood, the diagnosis should be entertained. This patient with an ES of cavernous sinus may be the first reported case with a long-term follow-up in the literature.